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GD&TforBodyGD&TforBodyEngineering2Coursecontent•IntroductiontoGD&T•5StepProcessGD&TforBodyEngineering3Introduction•WhatisGD&T•HowitaffectsFordMotorCompanyGD&TforBodyEngineering4WhatisGD&T•GeometricDimensioningandTolerancingisatechnicaldatabasethroughwhichourProductDesignandManufacturingOrganisationscantalktooneanotherviaProductData,whetheronpaperorthecomputergraphicsscreen•Itistheengineeringproductdefinitionstandardthatgeometricallydescribesdesignintentandprovidesthedocumentationbaseforthedesignofthequalityandproductionsystem.•ItisatechniqueofcommunicationbetweenProductEngineeringandManufacturingEngineeringthatpromotesauniforminterpretationoftherequirementsformakingacomponent.GD&TforBodyEngineering5WhatisGD&T•GDTprovidesthedimensionsofthecomponentandthetolerancesinalanguagethateliminatesconfusingandinconsistentnotes,datumlines,andlocationpointidentifications,andreplacesthemwithstandardsymbolsthatrefertoauniversalcode.•Thiscodedescribesthedimensionsandtolerancesofthecomponentwithreferencetotherelationshipsofthefeaturestoeachotherandtheirfunctionalinterfaceswithmatingparts,assemblies,etc.GD&TforBodyEngineering6Authorisation•In1990FordWorld-wideadoptedtheAmericanNationalStandardforDimensioningandTolerancing,currentlytheASMEY14.5M1994.TheauthorisationfortheaboveisdocumentedinStandardD-1oftheFordEngineeringCADandDraftingStandardsandisreferencedonallourreleaseddata.•ThisinformationcanbeaccessedviaFordintranet;•TheabovedocumentalsocontainsanelectroniccopyoftheASMEY14.5M1994DimensioningandTolerancingStandard.GD&TforBodyEngineering7Application•TheapplicationofGDTisinitiallytheresponsibilityoftherelevantComponentEngineer,howeverteamworkisthekeytothecorrectapplicationthroughthecomponentCoreTeam.•Thisprovidestheopportunityforalldisciplinestocontributetheirpartofthetotaldesignpackage.•Itensurespartdatawillsatisfydesignintentaswellasmanufacturingandinspectionrequirementsbasedonfunction,machinecapabilityandavailabletechnology.GD&TforBodyEngineering8Application•ItprovidestheopportunityforproperDatumselectionandhasthepotentialtosignificantlyreduceproductchanges,especiallythosechangesfollowingfinalproductrelease.•TheCoreTeamshouldconsistataminimumofrepresentativesfromProductEngineering,DesignEngineering,ManufacturingEngineering,andQualityEngineering.GD&TforBodyEngineering9Moreinformation•FordEngineeringCADandDraftingStandards•GDTApplication•InfluenceFitandFinish•ReduceReworks•IncreaseReliability•AffectsAssemblyProcess•ReducecostGD&TforBodyEngineering11The5StepProcess12345GD&TforBodyEngineering125StepProcess1UtilisethenewDesignConcept2EstablishmentoftheDatumReferenceFrame3EstablishGD&TControls4EstablishTolerances5FinalApprovalofGD&TonCadDataGD&TforBodyEngineering13Step1UtilisenewdesignconceptGD&TforBodyEngineering14Utilisenewdesignconcept•The1ststepinvolvesmakingdecisionsatthebasicdesignstagethatwillultimatelyeffectthedesign,manufactureandverificationofthefinalcomponent.•ThiscanonlybesuccessfullyachievedbytherelevantPDrepresentativeattendingtheMasterControlPlan(MCP)Meetings.GD&TforBodyEngineering15MasterControlPlanWhatisthepurposeoftheMCPmeetinginrelationtoPD•Toestablishacommonunderstandingfortheverificationprocessofthemajorpanels,e.g.Bodyside,Hood,DeckLid,Door,Roof,Underbody,etc.•Toobtainagreementatanearlystageofthedesignforthedatumreferenceframe,dieapproach,etc.WhoattendstheMeeting•PDandManufacturing,i.e.BodyEngineering,DCD,Stamping,BodyandAssembly.GD&TforBodyEngineering16MasterControlPlanWhenshouldtheMeetingtakeplace.•Initialdesignconceptstage,knowingthecomponentsparameterssuchassizeandfunctionCurrentmethodsuse;•Pastevidence,pastexperience,cansometimeshinderratherthanassistthenewdesignconceptResultofmeeting•MaybedocumentedinCAD,orpaperformGD&TforBodyEngineering17Step2EstablishDatumReferenceFrameGD&TforBodyEngineering18EstablishDatumReferenceFrame•AspartoftheMasterControlPlan(MCP)Processmeeting,BodyEngineeringandManufacturingagreedtothedefinitionoftheDatumFeaturesandtheirlocation.•PDhaveOwnershipoftheDatumFeatures.GD&TforBodyEngineering19DatumReferenceFrame(ReferencePocketGuide,Page8)ConsistsofasetofthreemutuallyperpendicularplanesThereferenceframeexistsintheoryonlyandisnotonthepartSufficientdatumfeaturesareusedtopositionthepartinrelationtotheDatumReferenceFrame.GD&TforBodyEngineering20DatumFeatures•Anactualfeatureofthepartusedtostage/positionthepartintheequipmentforpurposesofrelatingitsgeometrytotheDatumReferenceFrame.GD&TforBodyEngineering21PrimaryDatumPlane•AchievedbyestablishingaminimumofthreePointstodefineaplaneGD&TforBodyEngineering22PrimaryDatumPlane•PrimaryDatumPlaneshouldbeParalleltoDiePlaneGD&TforBodyEngineering23PrimaryDatumPlane•WhenDatumTargetAreasdefiningPrimaryDatumPlanearenotononesingleplanarsurface,theymustbecontrolledonetoanotherusingthePROFILEofaSURFACEgeometriccontrol.GD&TforBodyEngineering24Supportingapane